Answer:
0.017559
Step-by-step explanation:
Data provided:
Probability of Households Having cable TV, p₀ = 76% = 0.76
Therefore,
The probability that the Households not having cable TV = 1 - 0.76 = 0.24
Sample size, n = 225 households
sample proportions is less than 82% i.e p = 0.82
Now,
The standard error, SE =
or
SE =
or
SE = 0.02847
and,
or
or
Z = 2.107
therefore,
P(sample porportions < 0.82) = P(Z < 2.107)
now from the p value from the Z table
we get
P(sample porportions < 0.82) = 0.017559
Answer:
The mathematical expectation of a student who purchases 10 tickets is -$39.65.
Step-by-step explanation:
A student that purchases 10 tickets out of 2900 has a probability of winning the cruise that can be calculated as:
Each ticket cost $5, so he has spent $50 for the 10 tickets.
Then, the expected value of this operation is equal to the expected value of the earnings (probability of winning the prize multiplied by the value of the prize), minus the costs:
The mathematical expectation of a student who purchases 10 tickets is -$39.65.
Answer: 0.002718
Step-by-step explanation:
Given : The population mean annual salary for environmental compliance specialists is about $62,000.
i.e.
Sample size : n= 32
Let x be the random variable that represents the annual salary for environmental compliance specialists.
Using formula , the z-value corresponds to x= 59000 will be :
Now, by using the standard normal z-table , the probability that the mean salary of the sample is less than $59,000 :-
Hence, the probability that the mean salary of the sample is less than $59,000= 0.002718